<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2012 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------

defined('THINK_PATH') or exit();
/**
 * Apachenote缓存驱动
 * @category   Extend
 * @package  Extend
 * @subpackage  Driver
 * @author    liu21st <liu21st@gmail.com>
 */
class CacheApachenote extends Cache {

	/**
	 * 架构函数
	 * @param array $options 缓存参数
	 * @access public
	 */
	public function __construct($options=array()) {
		if(!empty($options)) {
			$this->options =  $options;
		}
		if(empty($options)) {
			$options = array (
                'host'        =>  '127.0.0.1',
                'port'        =>  1042,
                'timeout'     =>  10,
			);
		}
		$this->options  =   $options;
		$this->options['prefix']    =   isset($options['prefix'])?  $options['prefix']  :   C('DATA_CACHE_PREFIX');
		$this->options['length']    =   isset($options['length'])?  $options['length']  :   0;
		$this->handler = null;
		$this->open();
	}

	/**
	 * 读取缓存
	 * @access public
	 * @param string $name 缓存变量名
	 * @return mixed
	 */
	public function get($name) {
		$this->open();
		$name  =   $this->options['prefix'].$name;
		$s     =   'F' . pack('N', strlen($name)) . $name;
		fwrite($this->handler, $s);

		for ($data = ''; !feof($this->handler);) {
			$data .= fread($this->handler, 4096);
		}
		N('cache_read',1);
		$this->close();
		return $data === '' ? '' : unserialize($data);
	}

	/**
	 * 写入缓存
	 * @access public
	 * @param string $name 缓存变量名
	 * @param mixed $value  存储数据
	 * @return boolen
	 */
	public function set($name, $value) {
		N('cache_write',1);
		$this->open();
		$value  =   serialize($value);
		$name   =   $this->options['prefix'].$name;
		$s      =   'S' . pack('NN', strlen($name), strlen($value)) . $name . $value;

		fwrite($this->handler, $s);
		$ret = fgets($this->handler);
		$this->close();
		if($ret === "OK\n") {
			if($this->options['length']>0) {
				// 记录缓存队列
				$this->queue($name);
			}
			return true;
		}
		return false;
	}

	/**
	 * 删除缓存
	 * @access public
	 * @param string $name 缓存变量名
	 * @return boolen
	 */
	public function rm($name) {
		$this->open();
		$name   =   $this->options['prefix'].$name;
		$s      =   'D' . pack('N', strlen($name)) . $name;
		fwrite($this->handler, $s);
		$ret    = fgets($this->handler);
		$this->close();
		return $ret === "OK\n";
	}

	/**
	 * 关闭缓存
	 * @access private
	 */
	private function close() {
		fclose($this->handler);
		$this->handler = false;
	}

	/**
	 * 打开缓存
	 * @access private
	 */
	private function open() {
		if (!is_resource($this->handler)) {
			$this->handler = fsockopen($this->options['host'], $this->options['port'], $_, $_, $this->options['timeout']);
		}
	}

}